Deep brain stimulation (DBS) is an FDA approved therapy for essential tremor and Parkinson's disease that provides symptomatic relief over long term. It is also a promising therapy for epilepsy, dyskinesias, obsessive-compulsive and anxiety disorder. However, the efficacy of the DBS therapy is significantly reduced due to difficulties in precisely localizing the stimulation microelectrodes. In addition, lengthy surgical sessions under anesthesia that include electrophysiological observations and radiological methods are often necessary to confirm the microelectrode location. The overall goal of this proposed project is to develop a microactuated microelectrode technology that will enable precise positioning and movement of microelectrodes in behaving animals after implantation for deep brain stimulation. The proposed technology will provide an unprecedented ability to monitor single neuronal electrical activity and behavioral correlates to stimulation in unanesthetized animals while the stimulation electrode is being moved towards the desired target structure. The above capability promises to greatly enhance the precision, efficacy and safety of DBS with implanted microelectrodes. Specifically, we propose to develop a thermal microactuator and associated microelectrode technology for precise positioning and optimal stimulation of the nigro-striatal bundle in behaving rat models of Parkinson's disease. The key technological barriers that must be overcome are (i). Developing microactuator technologies with enough translation capability to interrogate deep brain structures in rodents with sufficient precision in displacement (ii). Development and optimization of an integrated stimulation and recording capability in the nigro-striatal bundle using an array of microactuated microelectrodes. The proposed technology will be tested and validated in rodent models of Parkinson's disease. Successful development of this technology will make microelectrode implantation for deep brain stimulation precise leading to safe and an efficient therapy with shorter surgical times. Future developments of this technology could lead to an efficient delivery vehicle for drug or gene therapy.